To determine whether the effects of Spy1 overexpression on ERK1/2 could be mediated through RIPK2, cells were transfected with Myc-tagged-Spy1 followed by infection with lentivirus packaging either scrambled control shRNA (pLKO) or shRNA targeting two different regions of the RIPK2 mRNA (shRIPK2.1, shRIPK2.2) (Figure 4D). Here, SPDYA is linked to infection.